1. Field of the Invention
The present invention relates to a picture signal processing circuit, a picture signal processing method, an imaging apparatus, a display device, and a camera system that are preferable when they are applied to the case of imaging high-resolution pictures, for example.
2. Background Art
Recently, with improvements in performance of imaging devices such as imaging sensors, the number of pixels in pictures imaged using an imaging apparatus such as a video camera or a still camera has been increased. Typically, a photographer brings a subject into focus while looking into a small viewfinder monitor provided on or connected to the imaging apparatus, and takes an image of the subject. However, since the display range of the viewfinder monitor is small, the number of displayed pixels of the viewfinder monitor is smaller than the number of effective pixels of the imaging device. Accordingly, for display of pictures on the viewfinder monitor, the number of pixels of the pictures supplied from the imaging device has been down-converted into the number of pixels that the viewfinder monitor can display.
FIGS. 10A and 10B show examples of pictures displayed on a viewfinder monitor in the past.
FIG. 10A shows an example of picture size that an imaging apparatus can image.
The imaging apparatus in this example can image a picture having a picture size of 1920×1080 pixels based on HD (High-Definition) standards.
FIG. 10B shows an example of a picture displayed on the viewfinder monitor.
The viewfinder monitor can display a picture in picture size of 960×540 pixels, and the picture size of the viewfinder monitor is only a quarter of the picture size (1920×1080 pixels) of the picture that the imaging apparatus shown in FIG. 10A can image. Accordingly, the viewfinder monitor is not able to display the picture unless the picture size of the picture imaged in HD (1920×1080 pixels) is reduced to the picture size of 960×540 pixels. The reducing processing of the picture size is performed by thinning pixels of the picture imaged in the imaging apparatus or using various kinds of filters on the picture signals. For example, when a typical digital filter is used, processing of filtering of (1,1) is performed on the picture signals.
JP-A-2005-191702 discloses a technology related to a viewfinder monitor attached to the imaging apparatus.